[tobeychris]

Telus has kid find, but it's not that accurate.
TomTom also has a buddy feature, but that would require the daughter to update her position I believe.
I think there's an application that can be used to track you cell, but I'll have to let someone else post it, it was posted a while ago, in order for you to find your lost phone.

As for the ##diag#, it depends what ROM you're on.